Earthquake load calculations as per IS1893-2002.- by Hemant Vadalkar .

Project : Building xyz at Mumbai. Rev.Mar2003

User : hsv Date : 30-Apr-14

(1) TOTAL SEISMIC WEIGHT OF BUILDING ( W ) = 19250 TONS

? (2) Height of the building h (metre) = 20

? (3) Base dimension of the building d (metre) = 10

? (4) Building Type 1: Bldg. with infill 1 0.569

2 : RCC frame Bldg. without infill 0.709

3 : Steel frame Bldg. without infill 0.804

? (4a) Soil strata 1: Hard, 2: Medium, 3: Soft 2

(5) Time period T (T1 = 0.09 * h / sqrt(d)= 0.569 seconds

T2 = 0.075*h^0.75 ; T3 = 0.085*h^0.75 )

? (6) Zone factor Z as per Table 2 = 0.16

? (7) Importance Factor I as per Table 6 = 1

? (8) Response Reduction Factor R as per Table 7 = 5

(9) From Fig 2 of IS:1893-2002 Sa/g = 2.389

(10) Design Horizontal Seismic coefficient Ah

(11) Ah =Z*I*Sa/(2*R*g) = 0.0382

(12) DESIGN BASE SHEAR ( Vb = Ah * W ) = 736 TONS

? (13) TYPICAL STOREY HEIGHT ( H ) = 2.9 METRES

(14) P_FACTOR = (Wi*hi^2) / (TOTAL(Wi*hi^2))

(15) Qi = P_FACTOR * Vb

FLOOR Wi hi Wi*hi^2 P_FACTOR Qi NO. OF JOINT

(TONS) (MTS) (TONS) JOINTS FORCE

(TONS)

===== ====== ======= =========== ======== ========= ====== =========

ROOF 1000 79.82 6371232 0.1413 104.0 1 104.0086

25 700 76.92 4141680 0.0919 67.6 1 67.6118

24 700 74.02 3835272 0.0851 62.6 1 62.6098

23 700 71.12 3540638 0.0785 57.8 1 57.7999

22 700 68.22 3257778 0.0723 53.2 1 53.1823

21 700 65.32 2986692 0.0663 48.8 1 48.7569

20 700 62.42 2727379 0.0605 44.5 1 44.5237

19 700 59.52 2479841 0.0550 40.5 1 40.4827

18 700 56.62 2244077 0.0498 36.6 1 36.6339

17 700 53.72 2020087 0.0448 33.0 1 32.9774

16 700 50.82 1807871 0.0401 29.5 1 29.5130

15 700 47.92 1607428 0.0357 26.2 1 26.2408

14 700 45.02 1418760 0.0315 23.2 1 23.1609

13 700 42.12 1241866 0.0275 20.3 1 20.2731

12 700 39.22 1076746 0.0239 17.6 1 17.5776

11 700 36.32 923400 0.0205 15.1 1 15.0742

10 700 33.42 781827 0.0173 12.8 1 12.7631

9 700 30.52 652029 0.0145 10.6 1 10.6442

8 700 27.62 534005 0.0118 8.7 1 8.7175

7 700 24.72 427755 0.0095 7.0 1 6.9830

6 700 21.82 333279 0.0074 5.4 1 5.4407

5 700 18.92 250576 0.0056 4.1 1 4.0906

4 700 16.02 179648 0.0040 2.9 1 2.9327

3 700 13.12 120494 0.0027 2.0 1 1.9670

2 700 10.22 73114 0.0016 1.2 1 1.1936

1 700 7.32 37508 0.0008 0.6 1 0.6123

STILT 575 3.66 7702 0.0002 0.1 1 0.1257

Base 175 0.00 0 0.0000 0.0 1 0.0000

===== ====== ======= =========== ======== ========= ====== ========= ==

TOTAL 19250 45078687 1.0000 735.9(W) MT (Vb) MT

Approximate Seismic weight calculations :

(I) TYPICAL FLOOR BEAM+COL SELF WT(DL) = 175.00 TONS

(II) TYPICAL FLOOR SLAB (DEAD) LOADS = 100.00 TONS

(III) TYPICAL FLOOR WALL (DEAD) LOADS = 400.00 TONS

(IV) TYPICAL FLOOR SLAB (LIVE) LOADS = 100.00 TONS

(V) ROOF FLOOR SLAB (DEAD) LOADS = 170.80 TONS

(VI) ROOF FLOOR SLAB (LIVE) LOADS = 0.00 TONS

(VII) GR. / PLINTH LEVEL D.L. (NO L.L.) = 575.00 TONS

(VIII) TYPICAL FLOOR D.L. + (25%) L.L. = 700.00 TONS

(IX) ROOF FLOOR D.L. + (25%) L.L. = 345.80 TONS

Earthquake load calculations as per IS1893-2002.

Calculation of Time period T sec

T=0.075h^0.75

T=0.085h^0.75

Buildings with Brick infill panels

Bldg. Without Brick infill Base dimension d (m) T= 0.09*h/d^0.5

Height

h(m)

RC frame Steel

frame 10 20 30 40 50 60

0 0 0 0 0 0 0 0 0

5 0.2507776 0.284215 0.142302 0.100623 0.082158 0.071151 0.06364 0.058095

10 0.421756 0.47799 0.284605 0.201246 0.164317 0.142302 0.127279 0.11619

15 0.5716493 0.647869 0.426907 0.301869 0.246475 0.213454 0.190919 0.174284

20 0.7093062 0.80388 0.56921 0.402492 0.328634 0.284605 0.254558 0.232379

25 0.8385255 0.950329 0.711512 0.503115 0.410792 0.355756 0.318198 0.290474

30 0.9613958 1.089582 0.853815 0.603738 0.49295 0.426907 0.381838 0.348569

35 1.0792257 1.223123 0.996117 0.704361 0.575109 0.498059 0.445477 0.406663

40 1.1929061 1.35196 1.13842 0.804984 0.657267 0.56921 0.509117 0.464758

45 1.3030787 1.476823 1.280722 0.905608 0.739425 0.640361 0.572756 0.522853

50 1.4102262 1.598256 1.423025 1.006231 0.821584 0.711512 0.636396 0.580948

55 1.5147232 1.716686 1.565327 1.106854 0.903742 0.782664 0.700036 0.639042

60 1.6168685 1.832451 1.70763 1.207477 0.985901 0.853815 0.763675 0.697137

65 1.7169051 1.945826 1.849932 1.3081 1.068059 0.924966 0.827315 0.755232

70 1.8150341 2.057039 1.992235 1.408723 1.150217 0.996117 0.890955 0.813327

75 1.9114248 2.166281 2.134537 1.509346 1.232376 1.067269 0.954594 0.871421

80 2.0062209 2.273717 2.27684 1.609969 1.314534 1.13842 1.018234 0.929516

85 2.0995463 2.379486 2.419142 1.710592 1.396693 1.209571 1.081873 0.987611

90 2.1915084 2.48371 2.561445 1.811215 1.478851 1.280722 1.145513 1.045706

95 2.2822014 2.586495 2.703747 1.911838 1.561009 1.351874 1.209153 1.1038

100 2.3717082 2.687936 2.84605 2.012461 1.643168 1.423025 1.272792 1.161895

105 2.4601027 2.788116 2.988352 2.113084 1.725326 1.494176 1.336432 1.21999

110 2.5474506 2.887111 3.130655 2.213707 1.807484 1.565327 1.400071 1.278085

115 2.6338112 2.984986 3.272957 2.31433 1.889643 1.636479 1.463711 1.336179

120 2.7192379 3.081803 3.41526 2.414953 1.971801 1.70763 1.527351 1.394274

125 2.803779 3.177616 3.557562 2.515576 2.05396 1.778781 1.59099 1.452369

130 2.8874786 3.272476 3.699865 2.6162 2.136118 1.849932 1.65463 1.510464

135 2.9703771 3.366427 3.842167 2.716823 2.218276 1.921084 1.718269 1.568558

140 3.0525114 3.459513 3.98447 2.817446 2.300435 1.992235 1.781909 1.626653

145 3.1339154 3.551771 4.126772 2.918069 2.382593 2.063386 1.845549 1.684748

150 3.2146205 3.643237 4.269075 3.018692 2.464752 2.134537 1.909188 1.742843

70 80

0 0

0.053785 0.050312

0.107571 0.100623

0.161356 0.150935

0.215141 0.201246

0.268926 0.251558

0.322712 0.301869

0.376497 0.352181

0.430282 0.402492

0.484068 0.452804

0.537853 0.503115

0.591638 0.553427

0.645423 0.603738

0.699209 0.65405

0.752994 0.704361

0.806779 0.754673

0.860565 0.804984

0.91435 0.855296

0.968135 0.905608

1.02192 0.955919

1.075706 1.006231

1.129491 1.056542

1.183276 1.106854

1.237062 1.157165

1.290847 1.207477

1.344632 1.257788

1.398417 1.3081

1.452203 1.358411

1.505988 1.408723

1.559773 1.459034

1.613559 1.509346

0

0.5

1

1.5

2

2.5

3

3.5

4

0 20 40 60 80 100 120 140 160

Tim

e p

eri

od

T s

ec

Height h (m)

Time period v/s height

A : RC frames without infill B : Steel frames without infill

A

B

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 20 40 60 80 100 120 140 160

Tim

e p

eri

od

T S

ec.

Height h (m)

Height v/s time period

A : RC frames without infill panels

B: Steel frames without infill panel

D 10 : Bldg. with infill & Base 10m

D 20 : Bldg. with infill & Base 20m

D 30 : Bldg. with infill & Base 30m

D40 : Bldg with infill &Base 40m

A

B

D 10

D 20

D 30

D 40

For A : T = 0.075 * h0.075 For B : T = 0.085 * h0.075 For others T = 0.09 * h / (d0.5)

Help on the work sheet : by Hemant Vadalkar

1 All the cells with yellow colour are for data input.

Numbers in blue colour are not protected & can be changed.

2 No macro is used in this sheet.

3 Earthquake base shear calculations are done as per new IS1893-2002.

4 Provide the required parameters like building height, base dimension,

soil strata, building type, zone factor, Importance factor etc.

5 Program will calculate the base shear Vb for the entire structure.

To calculate the seismic weight, provide DL+appropriate fraction of LL

for every floor and height of floor. This is required to calculate the

distribution of EQ forces along the height of the building.

6 Reference may be made to IS1893-2002 for the different parameters.

7 Values of Zone factor Z are given at the location Col:AC Row:7 in sheet EQCalc.

8 At location, Column:O , Row:1, approximate column selfweight calculation

can be carried out based on column sizes at different floors in sheet EQCalc.

9 Graphs of Time period T v/s Height H can be viewed in sheet "Chart1"

for RCC and steel frames without infill panels.

Sheet named " Chart2" shows graph of T v/s H for RCC frames with infill panels

for different base dimensions like 10m, 20m,30m and 40m.

10 For suggestions and comments contact Hemant Vadalkar at Email: vva@vsnl.com